Drawing board



June 4, 1935. R. 1.. SORENSEN 2,003,841

DRAWING BOARD Original Filed Aug. 13, 1931 l l; /111 VII/A III/III IIIII/ IIIIII/IIIIII INVENTOR UNITED STATES PATENT OFFICE DRAWING BOARD Rasmus L. Sorensen, Cincinnati,.0hio

Application August 13,

1931, Serial No. 556,840

Renewed December 1, 1934 1 Claim.

This invention relates to drawing boards and is particularly directed to a small portable type of drawing board including improvements in the attachment or mounting of the straight edge element relative to the drawing surface of the board.

It is an object of this invention to provide an improved portable drawing board which efiiciently and readily contains the various drawing instruments and in which the straight edge element 0 is a permanently fixed part adjustably mounted on the face of the board, whereby the drawing board and instruments are a compact unit of great utility in that class of work where it is necessary to transport this equipment from place to place.

It is another object of this invention to provide an improved attachment means and mounting for the straight edge element as a non-detachable part of the board, which mounting is simple and highly efficient for maintaining the straight edge element in aligned positions across the face of the board and for permitting its free move ment between and in parallelism with the upper to the lower edges of the board and to further include this improved mounting and attachment means within the confines of the board, whereby it is impossible to foul or disturb the same.

Other objects and certain advantages will be more fully apparent from a description of the accompanying drawing, in which:

Figure l is a perspective view of the improved drawing board showing it in open position for permitting access to the instruments.

Figure 2 is a perspective view of the board in closed position or position of use.

Figure 3 is a sectional View taken on line 33. Figure 2, illustrating the association of the foldable parts of the board and the contained mechanism and instruments.

Figure 4 is a sectional view taken on line 44, Figure 2, illustrating the mounting or connection of the straight edge element to the alignment maintaining cable mounted below the drawing surface of the board.

The drawing board described in general comprises sections or slabs hinged together. These sections include recesses or depressions on their abutting faces, which recesses are designed for containing the drawing instruments customarily used and for housing the aligning and mounting device for the straight edge element disposed across the face of the drawing board.

Referring to the drawing, the sections or slabs of the board are indicated at 5 and 6 and the hinges joining them at 1. Each section includes a recess 8 over substantially its entire inner face providing rims or walls 9 abutting when thesections are closed upon each other. The sections are of substantial thickness to permit the reduction F caused by the recesses. Complementary latch parts I0 and H are included at adjacent points on the respective sections on those edges opposite to the hinges, whereby the board may be secured in closed position when in use and transportation.

Within the recessed face of the section 5, a plurality of lugs 12 are formed. These lugs are adapted to maintain the various instruments against lateral displacement and are arranged according to the outline of the particular instrument. In the present instance a measuring device l8, a angle I9, a angle 20, and a protractor 2! are contained within the recess.

Felt pads I3 are included under the instruments for preventing the same from rattling or shaking about. In the recess formed in the section 6, a plurality of lugs M are included, one for each instrument. The lugs l4 include felt pads l3 therein. When the sections 5 and 6 are superposed, these lugs engage the central portions of the respective instruments and rigidly maintain them in position.

The section 6 contains the straight edge attachment and control mechanism. For the purpose of this mechanism the section 6 includes slots i5, one at each side edge of the board, these slots extending through into the recess and being for the purpose of attachment of the straight edge to the mounting device.

For the purpose of attaching and maintaining the straight edge element IS in aligned position and permitting movement thereof from the upper edge of the board to the lower, an endless cable I! is used. This cable is mounted on pulleys 22. A pulley is disposed in each corner of the recess. The means for mounting the pulleys may be of any eflicient form, a screw being used in the present instance. By the arrangement of the pulleys, portions 23 of. the cable length are disposed directly beneath and parallel to the slots. For the purpose of permitting movement of these cable portions beneath the slots and in the same direction, the length of cable is crossed from the respective sides. The ends of the straight edge element 16 are attached to the respective lengths of cable beneath the slots.

A screw 24 is provided extended through the end of the straight edge. A sleeve 25 surrounds the screw and has a flange 26 on its inner end preventing outward displacement of the sleeve through the slot, these sleeves being adapted to U traverse the length of the slots. A washer 21 and a nut 28 on the screw are adapted. for clamping the portion of cable length against the underside of the sleeve. Therefore, by this arrangement, actuation of the straight edge at the will of the draftsman moves the portions of the cable lengths in the same direction by the crossed arrangement, reverse movements of the ends of the straight edge element and the portions of the cable being prevented. It is impossible to cant the straight edge element or disalign the same relative to the upper and lower edges of the board, but at the same time the straight edge element is permanently fixed in position 01'. use on the board.

As an aid to the draftsman, in placing the paper on the board, there is an upstandinglip 29 at the lower edge of the board on the drawing surface thereof and a pair of clips 38 are attached in position relative to this edge including spring portions acting downwardly against the surface of the board whereby the paper may be slipped under the clips and against the lip, which lip constitutes a straight edge in parallelism with the straight edge element.

The board may be made of Wood or preferably of composition for reduction in parts and affords a very convenient instrumentality for draftsmen who require a small portable board with a complete set of instruments capable of being carried about as a unit without bother.

Having described my invention, I claim:

In a device of the class described, superimposed slabs hinged together, a straight edge element disposed across the outer face of one of said slabs, the inner face of said slab having a recess therein, an endless cable contained in said recess, pulleys in the recess mounting said cable, said cable disposed on said pulleys with portions of the length thereof movable in the same direction and respectively disposed adjacent and along the side edges of said slab on which the straight edge element is mounted, and attaching devices extending through slots adjacent the side edge of said slab securing the ends of said straight edge element respectively to said portions of the v cable, said second slab forming with the first slab, a housing whereby the cable and pulleys are enclosed between the slabs, the straight edge element being maintained by said cable to move in parallelism to itself,

RASMUS L. SORENSEN. 

